Manufacturing processes of thin film transistor substrates (TFT substrates) for use in, e.g., LCD devices typically include a process of exposing a photoresist to light to pattern each layer. In this process, a division exposure method is often used to accurately pattern each layer. The division exposure method is a method in which a TFT substrate is divided into a plurality of exposure regions to be exposed by a division exposure system.
When using such a division exposure method, a displacement of a pattern (a displacement of a pattern in a layer) and/or an overlay misalignment (a pattern misalignment between layers) sometimes occurs at the boundary between the divided exposure regions due to manufacturing variation. If such a displacement of a pattern and/or an overlay misalignment occurs, the parasitic capacitance between electrodes, and the like vary at the division boundary. If the parasitic capacitance varies in this manner, a voltage that is applied to the liquid crystal layer also varies accordingly, whereby the light transmittance of the pixels varies at the division boundary. If the light transmittance varies in this manner, that region is visually recognized as display unevenness, which adversely affects display quality of LCD devices.
As a solution to this problem, Patent Document 1, for example, discloses a technique of making display unevenness less visually recognizable by randomly positioning pixels having different transmittances near the division boundary.
In recent years, there has been a strong need to increase brightness of display devices, and the like. In response to this need, multi-domain vertically aligned mode liquid crystal display devices (MVA-LCDs) having excellent viewing angle characteristics have been studied and developed by vertically aligning liquid crystal molecules having negative dielectric anisotropy, and providing protrusions and/or slits on substrates as a structure for controlling alignment of the liquid crystal molecules. As disclosed in Patent Document 2, a polymer sustained alignment (PSA) technique is effective in enabling both higher brightness and faster response to be implemented in the MVA-LCDs. In the PSA technique, a liquid crystal composition, which contains a polymerizable component such as a monomer or an oligomer in a liquid crystal material, is sealed between substrates. A voltage is applied between the substrates to tilt liquid crystal molecules, and in this state, the monomer or the like is polymerized to form a polymer. This provides a liquid crystal layer that is tilted in a predetermined tilt direction by application of a voltage, whereby the tilt direction of the liquid crystal molecules can be defined.